This question is actually related to my earlier question ("what is motion").
The fact that objects move a lot in the universe and that the universe is expanding, can imply that gravity is a repulsive force that increases with distance.. so the farthest objects repel us more.

This can still explain several existing observations, e.g., why does the apple fall?

Motion is the result of such repulsion. Two objects unlucky enough not to be moving relative to each other get squished due to the repulsion of the rest of the universe around them. The earth repels the apple less than the stars so it is pushed towards the earth.

Furthermore, it can explain the expanding universe without the need for dark energy.

This could be demonstrated in a thought experiment. If we take a lot of same-charge particles (with small mass) such as electrons and lock them in a large box at a low enough temperature. The mutual repulsion of the particles may cause similar motion as if due to gravitational attraction.

Another experiment would be to measure the slight changes in our weight during day and night when the sun and earth align (if their masses are large enough to detect the feeble change in repulsion).

[EDIT: the question in the original form may not have been clear. It is "can we model".. with a yes/no answer and why (not). If downvoting, please justify.

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If the stars push the apple to the Earth, wouldn't the stars on the other side of the Earth push it back up with an equal force? Or maybe you're a flat-Earthist?
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Pete JacksonAug 5 '11 at 21:52

Interestingly, this theory has been proposed earlier (Le Sage theory). According to wikipedia, mainstream scientists discount this theory for lack of experimental evidence. So this answers the question.

Suggestion to the answer(v1): If you mention the words Le Sage theory explicitly in the answer, then it would become a searchable keyword for future visitors to find this post.
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Qmechanic♦Jan 11 '13 at 18:31